<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script>
			function calculate(method, ...mums){
				let result;
				if(!method\\nums.length == 0){
				alert('请传入参数!');
				return;
			}
			if(method == '*'){
				result = 1;
				for(let i = 0; i< nums.length; i++){
					result * = nums[i];
				}
			}else if(method == '+'){
				result = 0;
				for(let i = 0; i < nums.length; i++) {
					result += nums[i];
				}
			}
			alert(result);
			}
			calculate("+",1,2);//3
			calculate("+",1,2,3,4,5);//15
			calculate("*",1,2,3);//6
			calculate("*",1,2,3,4,5);//120

		</script>
	</body>
</html>
